Description of Campaign
Researchers identified a series of campaigns distributing Remcos and NanoCore RATs masquerading as the Kingdom of Saudi Arabia (KSA) embassy in Manila and the Philippine Overseas Employment Administration (POEA) in mid-2021. Upon further investigation, Proofpoint identified additional, separate campaigns distributing the same malware masquerading as the Philippine Department of Health and Bureau of Customs. It is likely that the threat actor is attempting to gain remote access to target computers, which could be used for information gathering or to install follow-on malware or engage in business email compromise (BEC) activity.
Proofpoint separated campaigns into two distinct threat activity clusters. In all cases, message lures were in English. They contained multiple threat distribution mechanisms including:
OneDrive URLs linking to RAR files with embedded UUE files.
PDF email attachments with an embedded OneDrive link or other malicious URL leading to compressed executables (.iso files) that download and run malware.
Compressed MS Excel documents containing macros which, if enabled, download malware.
Remcos is a commodity remote access tool available for purchase online. NanoCore is also commodity malware and written in .NET by "Aeonhack". The code is obfuscated with Eazfuscator.NET 3.3. NanoCore RAT is sold on various hack forums. NanoCore includes many features and plugins. Both Remcos and NanoCore RAT are distributed by numerous cybercrime threat actors with many different delivery techniques and lures.
The McAfee Enterprise ATR Team gathers and analyzes information from multiple open and closed sources before disseminating intelligence reports. This campaign was researched by Proofpoint and shared publicly here.
How to use this article:
- If a Threat Hunting table has been created, use the rules contained to search for malware related to this campaign.
- Review the product detection table and confirm that your environment is at least on the specified content version.
To download the latest content versions, go to the Security Updates page.
- Scroll down and review the "Product Countermeasures" section of this article. Consider implementing them if they are not already in place.
- Review KB91836 - Countermeasures for entry vector threats.
- Review KB87843 - Dynamic Application Containment rules and best practices.
- Review KB82925 - Identify what rule corresponds to an Adaptive Threat Protection and Threat Intelligence Exchange event.
This Knowledge Base article discusses a specific threat that is being tracked. The list of IOCs will change over time; check MVISION Insights for the latest IOCs.
Campaign IOC
| Type |
Value |
| SHA256 |
DE5992F7C92351D1011FBECE2D4BF74ECFC3B09F84AEDB12997A2C3BF869DE2C |
| SHA256 |
098FE3C8D0407E7438827FB38831DAC4AF8BD42690F8BD43D4F92FD2B7F33525 |
| DOMAIN |
shahzad73.casacam.net |
| DOMAIN |
shahzad73.ddns.net |
| DOMAIN |
cato.fingusti.club |
| DOMAIN |
remcos.got-game.org |
Minimum Content Versions:
| Content Type |
Version |
| V2 DAT (VirusScan Enterprise) |
10154 |
| V3 DAT (Endpoint Security) |
4606 |
Detection Summary
| IOC |
Scanner |
Detection |
| DE5992F7C92351D1011FBECE2D4BF74ECFC3B09F84AEDB12997A2C3BF869DE2C |
AVEngine V2 |
RAT/Remcos.a |
| AVEngine V3 |
RAT/Remcos.a |
| JTI (ATP Rules) |
JTI/Suspect.196612!a917ef9e2364 |
| RP Static |
- |
| RP Dynamic |
- |
| IOC |
Scanner |
Detection |
| 098FE3C8D0407E7438827FB38831DAC4AF8BD42690F8BD43D4F92FD2B7F33525 |
AVEngine V2 |
AgentTesla-FDCE!68CDFBBC7A43 |
| AVEngine V3 |
AgentTesla-FDCE!68CDFBBC7A43 |
| JTI (ATP Rules) |
JTI/Suspect.196612!68cdfbbc7a43 |
| RP Static |
- |
| RP Dynamic |
- |
Minimum set of Manual Rules to improve protection to block this campaign
IMPORTANT: Always follow best practices when you enable new rules and signatures.
When you implement new rules or signatures, always set them to Report mode first and check the alerts generated. Resolve any issues that arise and then set the rules to Block. This step mitigates against triggering false positives and allows you to refine your configuration.
For more information, see KB87843 - List of and best practices for Endpoint Security Dynamic Application Containment rules.
Endpoint Security - Advanced Threat Protection:
Rule ID: 4 Use GTI file reputation to identify trusted or malicious files
Aggressive set of Manual Rules to improve protection to block this campaign
IMPORTANT: Always follow best practices when you enable new rules and signatures.
When you implement new rules or signatures, always set them to Report mode first and check the alerts generated. Resolve any issues that arise and then set the rules to Block. This step mitigates against triggering false positives and allows you to refine your configuration.
For more information, see KB87843 - List of and best practices for Endpoint Security Dynamic Application Containment rules.
Virusscan Enterprise - Access Protection Rules:
Prevent creation of new executable files in the Windows folder
Host Intrusion Prevention:
Rule ID: 6011 Generic Application Invocation Protection
Rule ID: 1148 CMD Tool Access by a Network Aware Application
Rule ID: 6010 Generic Application Hooking Protection
